Audio loggers are well known devices that are used for the purpose of obtaining records of voice communication by recording audio on a tape. They have particular use in police stations, hospitals, prisons, brokerage houses and other locations where there is a need to record a conversation or other audio and the time and date thereof. Upon completion of recording, the tapes upon which audio is written are stored for archival purposes. The tapes can be either digital tapes or analog tapes, depending upon whether a digital audio logger or analog audio logger is used.
One requirement for a logger is that there be an ability to have audio retrieved even though a tape is still having audio written thereon. Clearly, if a tape had to be repositioned in order to obtain audio, there would be an interruption and data would be lost. In order to avoid such an occurrence, prior loggers have provided redundant tapes. One tape would act as a primary tape that receives data on a continuous basis while the second tape receives the same data simultaneously, except that the second tape could be removed when audio had to be retrieved. Upon removal of the secondary tape, another secondary tape would be installed in the logger and the redundancy is continued.
Although the redundancy scheme provides a way for obtaining data without interrupting recording, there clearly are disadvantages. One disadvantage is that an audio tape is a slow responding medium and searching for information on a tape is time consuming. This is a disadvantage during the time of emergencies. Another disadvantage is that a lapse in written data could occur during exchange of the secondary tapes. Clearly, it would be advantageous to be able to have continuous recording of audio without the disadvantages of using redundant tapes.